Pick-up trucks are a popular and relatively inexpensive means of transportation for passengers and for carrying small loads. However, the cargo area is an open box and is therefore subject to adverse weather while providing no security against theft. In addition, fuel economy is reduced due to the air drag effects on the open box.
Various attempts have been made to provide suitable covers for the backs of pick-up trucks. These range from a simple tarpaulin to more complicated rigid covers including folding types. Some earlier types of covers do not provide the degree of protection desired for the cargo or may be relatively complex or expensive. Likewise, some of the earlier covers do not provide the degree of access desired to load the truck or unload it.
The problem of covering open areas in vehicles has been recognised for some time and attempted solutions include the flexible cover for vehicles shown in U.S. Pat. No. 1,950,927 to McMillan. This patent shows a cover for an automobile including a plurality of slats connected together by flexible or hinged joints. The sides of the units are covered by fixed moldings. However, the cover requires a relatively intricated roller system to remove the cover. Pick-up trucks do not have a suitable location for such a roller unit without taking up valuable cargo area.
U.S. Pat. No. 2,140,960 to Kercher shows a sliding top for trucks. The unit is rigid and requires considerable room to open. Furthermore, the cover must be relatively heavy in order to provide the degree of rigidity required to support the top when it opens.
U.S. Pat. No. 2,942,658 to Wilson shows a foldable wall structure for buildings. The structure employs high hoods to provide protection at the sides of the cover while allowing clearance for the folded cover. This would be unsuitable for pick-up trucks where extensions to the sides of the box would be necessary, thus increasing the height for loading as well as adversely affecting the weight and appearance of the unit.
U.S. Pat. No. 3,570,579 to Matsushima et al shows a sliding cover consisting of a plurality of cover pieces linked with hinges. The assembly can be housed in the cabinet covered by the device.
Other patents of general interest include U.S. Pat. Nos. 3,140,563 to Allen; 1,696,208 to Marshall; 2,368,936 to McGehee; and 1,981,241 to McWilliams.
Such prior art does not reveal a cover having all the desired features for a pick-up truck. The cover should be capable of being unfolded or retracted without impinging upon the cargo area of the truck. Furthermore, it should offer the required degree of protection without being subject to lifting or other adverse effects due to wind at highway speeds. It should be simple so that it is reliable and can be made and sold as economically as possible.